Farsightedness and nearsightedness. Differences, symptoms and treatment

A study conducted in early 2020, showed that as many as 90% of Poles aged 18-65 have various eye and vision problems, and more than 60% have a diagnosed visual impairment. 69% of compatriots admit that the increased number of hours spent in front of screens (working and studying remotely!) has worsened the quality of their vision.

The most common diagnoses are nearsightedness (in 27% of cases), astigmatism (in 14% of cases) and farsightedness (in 11% of cases).

What kind of problems does a short-sighted person face?

• Short-sighted people see objects farther away indistinctly and to sharpen the image, they keep squinting.
• The higher the visual defect, the more difficult it is for him to see objects clearly even from the shortest distance.
• Short-sightedness cannot be cured pharmacologically, nor will it be reversed by wearing even the best-fitting glasses or contact lenses.
• Short-sightedness is often accompanied by astigmatism.
• High myopia, most often is genetically determined and one has no influence on its development.
• High myopia carries the risk of retinal detachment or degenerative and atrophic changes, so people with high myopia should avoid excessive exercise.
• The visual defect appears in adolescence and can progress rapidly.

What problems does a farsighted person face?

• Farsighted people have trouble seeing objects located close to their eyes clearly, but because they abuse the accommodative mechanism, eventually there is a problem seeing objects clearly from any distance.
• Farsighted people who are affected by a large visual defect may suffer from low vision.
• Farsighted (hyperopic) people often don’t even know about their visual defect – if the so-called amplitude of accommodation (the accommodative capacity of the eye) is high enough, they just see well on a daily basis until the moment when they begin to have problems with clearly perceiving objects from any distance (the accommodation mechanism becomes unregulated and begins to fail).
• Farsightedness is often accompanied by symptoms associated with asthenopia (a subjective feeling of weakness in the eyes caused by an uncorrected visual defect): eye fatigue, eye pain, headaches, nausea, tearing, burning.

None of the aforementioned vision defects can be cured pharmacologically. Nor does correction with glasses or contact lenses always have the desired effect.

Once the nearsightedness or farsightedness has stabilized, it is best to perform laser vision correction.

Techniques effective for laser myopia correction are:

• LASEK/PRK: The procedure involves either deflecting (LASEK) or removing (PRK) the upper cellular layer of the cornea (epithelium) and then appropriately reshaping the underlying corneal tissue with an excimer laser. The goal of the procedure is to properly model the central surface of the cornea with a laser beam so that it focuses the image precisely on the retinal surface.
• LASIK: a two-step technique; the cornea is incised with a scalpel (microkeratome), and then the corneal surface is modeled so that it can properly focus the image onto the retina.
• Femto-LASIK: using a precise femtosecond laser, the surgeon makes a cut in the cornea, creating a thin flap 0.1 mm thick – a flap. He uses an excimer laser to reshape the previously exposed cornea for a few seconds, then the flap is closed back up; it attaches and forms a protective corneal barrier.
• Trans-PRK smart surFace: The least invasive laser treatment for myopia. Dioptric correction is done in the first stage of the procedure, while the surgeon uses a high-precision excimer laser. PRK used to be the standard method of laser eye treatment, and LASIK replaced it because it involved less pain. However, the LASIK technique failed in patients whose corneas were too thin or irregular. Trans-PRK’s state-of-the-art capabilities helped optimize the procedure at the most important point.

In correcting hyperopia, the following are used:

• LASIK – a two-step technique in which the cornea is incised with a scalpel (microkeratome), and then the corneal surface is modeled so that it can properly focus the image onto the retina.
• FemtoLASIK – thanks to a precise femtosecond laser, the surgeon makes a cut in the cornea, creating a thin flap 0.1 mm thick – a flap. He uses an excimer laser to reshape the previously exposed cornea for a few seconds, then the flap is closed back up; it attaches and forms a protective corneal barrier.

Also, astigmatism undergoes laser correction. Methods involved include: LASIK (laser assisted in situ keratomileusis), LASEK/PRK and Femto-LASIK (All-Laser-LASIK).